1-Preheat your oven: Preheat your oven to 180°C (350°F) and pat the lamb shanks dry before seasoning them with salt and pepper.

2-Brown the lamb shanks: Heat 2 tbsp of olive oil in a heavy-based pot on high heat, then brown the lamb shanks in batches for about 5 minutes until they’re evenly browned, and drain any excess fat afterward.

3-Sauté the vegetables: Reduce the heat to medium-low and add the remaining 1 tbsp of olive oil. Sauté the onion and garlic for 2 minutes, then toss in the carrot and celery and cook for another 5 minutes until the onion turns translucent and sweet.

4-Add liquids and seasonings: Stir in the red wine, chicken stock, crushed tomatoes, tomato paste, thyme, and bay leaves, making sure everything mixes well.

5-Simmer the lamb shanks: Return the lamb shanks to the pot, ensuring they’re mostly submerged in the liquid, then bring it to a simmer. Cover and transfer to the oven to cook for 2 hours.

6-Finish cooking uncovered: After that, remove the lid and cook uncovered for another 30 minutes until the lamb is tender but still attached to the bone.

7-Prepare the sauce: Once the lamb is done, take it out and keep it warm while you handle the sauce. Discard the bay leaves and thyme sprigs, then strain the sauce into a bowl, pressing the vegetables to get all the liquid. Return the sauce to the pot and simmer it to reduce to a syrupy consistency if needed, and adjust the seasoning with salt and pepper.

8-Serve: Finally, serve the lamb shanks over mashed potatoes, polenta, or pasta, and spoon the sauce on top. Add fresh thyme leaves as a garnish if you like.